Good afternoon, i have a problem starting my node-red.
when I run the command to open "node-red", it shows me serial port COM4 error: Error: Opening COM4: File not found.
Before this error happened, I managed to perform an LED test connected with the Arduino and everything worked correctly, when I went to perform a test with the DHT22 sensor and then closed my Node-Red, this error appears.
The Arduino IDE works normally with the COM4 port, I can normally program the program on it and run it.
I want to open my Node-Red, how can I solve this?
Does device manager show you have a COM4?
Is there any application still open & accessing COM4 (e.g. is Arduino IDE still open when you start node-red)
Yes, the manager recognizes the COM4 input so much that I can run the program directly in the Arduino IDE.
There is no application open when I try to start Node-Red..
I would restart your PC - potentially something has a hold on the port.
Alternatively, try this: HOWTO: Identifying which process is using the serial port.
- what version of
node-red are you running?
- what does
npm list serialport show...
you did not CD into your
.node-red folder - look at my screenshot.
is the command to enter the folder right? I can't get into node-red CD
from your earlier screenshot i see your user name is
npm list serialport
ALSO - you never stated what version of node-red you are running - it is listed in the console when you start node-red (it is missing from the opt your first screenshot)
there's the error, how do I fix it?
Sorry, its a typo by me.
npm list serialport
ALSO - you never stated what version of node-red you are running - it is listed in the console when you start node-red (it is missing from the top your first screenshot)
ok, so do you have any arduino nodes in your flows?
use ctrl-f to search node-red flows for
Perhaps you have added a node and set it to use COM4?
Yes, I used Arduino node and configured to use COM4, how do I delete? I can't get into the dashboard
Its not dashboard (its the node-red editor)
start node-red in safe mode
find and delete, then deploy.
incredible friend, thank you very much you found the solution! thank you so much
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